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To address the shortcomings of existing authentication schemes in vehicle networks, which commonly suffer from key escrow issues, as well as the lack of consideration for lightweight deployment and secure rapid authentication of compute-constrained electronic control unit (ECU), a lightweight certificateless anonymous authentication and key agreement scheme without bilinear pairings was proposed for compute-unconstrained ECU networks. The authentication key pair was securely constructed by elliptic curve cryptography, anonymous authentication and key agreement were realized by lightweight methods such as hash functions and XOR operation. Additionally, a certificateless batch verification scheme was proposed to reduce the authentication costs for compute-constrained ECU networks. Finally, a security verification method based on the colored Petri net (CPN) and Dolev-Yao attacker model was proposed to evaluate the formal security of the proposed scheme. The proposed scheme is proved through security evaluation and performance analysis to effectively resist various types of attacks such as replay, spoofing, tampering, known key, known specific session temporary information attack, etc., with multiple security attributes, small computation and communication cost.

Infantile epileptic spasm syndrome (IESS) is a new concept proposed recently. IESS is a unique and age-specific refractory epilepsy syndrome. The recent advances in molecular biology, neuroimmunology and the in-depth study of anti-epileptic mechanism in antiepileptic drugs have led to the achievements in the definition and treatment of infantile epileptic spasm. At present, the use of traditional antiepileptic drugs is decreasing, while the use of new antiepileptic drugs is increasing. In this paper, based on the relevant literature in recent years, the authors discuss the pathogenesis, epidemiology, etiology, diagnosis, treatment, therapeutic drugs, clinical progress, efficacy, and safety of infantile epileptic spasm, hoping to introduce the latest status in research and achievements of IESS.

Objective To prepare a new type of molybdenum disulfide (MoS2)/sodium alginate (SA) nanocomposite gel, and evaluate its microstructure, physical and chemical properties as well as its hemostatic and antibacterial performances. Methods The nanocomposite gel was prepared with a two-step method. Firstly, MoS2 nanosheets were synthesized by hydrothermal method; secondly, 2% SA solution was prepared as a template, being added with different concentrations of MoS2 dispersion; and then the SA/MoS2-X gel was obtained by crosslinking with calcium ions after being mixed evenly. The microstructure of SA and SA/MoS2-X were observed by scanning electron microscopy (SEM). Fourier transform infrared spectrometer (FTIR) analysis was used to analyze the surface functional groups of the substance through calibrating various vibration peaks on the spectrum. The absorption of the substance to specific wavelengths were measured by ultraviolet-visible (UV-Vis) light absorption spectroscopy. The inhibitory effects against E. coli and S. aureus and the hemostatic effect of SA/MoS2-X gel were evaluated by photothermal antibacterial experiment and rat liver hemorrhage model, respectively. Results The SEM results showed that the fiber network of the SA/MoS2-X gel was a 3-D porous structure, with its pore size and density being different from those of pure SA gel, and MoS2 was attached to the surface of SA gel and evenly distributed. The UV-Vis absorption spectrum indicated that the absorption peak of SA/MoS2-X was significantly higher than that of SA at 808 nm. The photothermal antibacterial effects against E.coli and S.aureus were remarkably enhanced in the SA/MoS2-X gel group (containing 1 and 2 mg/mL MoS2, respectively) (P < 0.05). In addition, the hemostatic effect of SA/MoS2-X gel on liver hemorrhage model of SD rats was greatly improved as compared with the control group (P < 0.05). Conclusion The SA/MoS2-X gel prepared by the two-step method has good porosity and binding stability to MoS2, with further improved photothermal and physicochemical properties, and presents high antibacterial performance against E.coli and S.aureus as well as good hemostatic effectiveness.

SnO2 nanorods were grown on two kinds of seed layers formed from SnCl2·2H2O and SnO2 nanoparticles precursors, respectively, and used as one-dimensional electron transport materials to fabricate perovskite solar cell (PSCs). Effects of the seed layers on morphology, structure, optical properties of SnO2 nanorods and perovskite films, charge transfer at SnO2/perovskite interfaces as well as device performance were investigated by utilizing field emission scanning electron microscopy (SEM), X-ray diffraction (XRD), ultraviolet-visible-near infrared spectroscopy(UV-vis), steady-state photoluminescence spectroscopy (PL) and volt-ampere characteristic curves (J-V). The results show that more dense seed layers can be formed from SnO2 nanoparticles and SnO2 nanorods films formed from SnO2 nanoparticles are more smooth and uniform relative to those grown from SnCl2·2H2O. The perovskite films deposited on the former show better crystallization quality and higher light absorption. The maximum efficiency of the device based on the SnO2 nanorods is 12.93%. This work demonstrates that SnO2 nanoparticles are a kind of excellent seed layer material for growing SnO2 nanorods films, and lays foundation for the preparation of high-performance perovskite solar cells based on one-dimensional electron transport materials.

Objective To construct a three-dimensional of human hepatic functional unit through digital technology, and study its 3D shape and spatial adjoining relationship in order to understand the construction law of hepatic functional unit hepatic lobule cells. Methods We selected human hepatic lobule tissue, and used conventional paraffin serial sections, HE staining technology and microscope scanning to obtain hepatic lobule section in 4-μm thickness. We employed Photoshop software for image registration and used AMIRA software 2019.1 version for 3D reconstruction of hepatic functional unit which include hepatic lobule. Lobular contours, hepatic sinusoids, hepatocyte cords, central veins, interlobular arteries, veins and bile ducts were measured and studied for the tissue morphological parameters. Results A 3D digital model of the hepatic functional unit was reconstructed, and we founded that the contour of the hepatic lobule was irregularly round and blunt polygon structure with different edge lengths. The maximum diameter was 1 495.27 μm and the minimum diameter was 1 036.96 μm; The central vein of the hepatic lobule was not located in the middle of the hepatic lobule, at 322.38, 474.05, 878.7 and 880.16 μm, The hepatic sinusoids were interwoven vascular networks, which did not constitute a radial arrangement of blood vessel networks. Conclusion The Results of our 3D morphological study of hepatic lobule are different from the traditional anatomy textbooks and atlas, which not only update our knowledge of the structure of hepatic functional unit, and provide a 3D visualization image of the real human hepatic lobule structure. However, we think that the 3D morphology of hepatic functional unit structure is produced under the condition of hepatic lobule cell shaping development and reshaping redevelopment, therefore it provides a computer model for the 3D printing of hepatic lobule tissue cells.

Tough conductive carbon black/nylon66 (CCB/PA66) antistatic composites modified by maleic anhydridegrafted ethylene-vinyl acetate copolymer (EVA-g-MAH) were prepared by twin-screw extrusion and injection molding. The mechanical, melt flow, and antistatic properties of the composites were tested, and the fracture surface morphologies and crystallization behavior of the composites were observed and studied by scanning electron microscopy (SEM) and differential scanning calorimetry (DSC), respectively. The results showed that EVA-g-MAH has good compatibility with PA66. The antistatic properties of PA66 increased with the addition of CCB, however the toughness and processing ability of the composites decreased significantly. The addition of 10% EVA-g-MAH in the 8% CCB/PA66 blend resulted in a 75.4% and 45.1% increase in impact strength and elongation at break, respectively, while maintaining relatively higher tensile strength (50.5 MPa). When the mass fraction of EVA-g-MAH was 20%, the volume resistivity and surface resistance and of 8% CCB/PA66 decreased by 2 to 3 orders of magnitude to 4.3 x 107 Ω · cm and 6.5 x 106 Ω, respectively, due to the selective location of CCB particles in 8% CCB/EVA-g-MAH/PA66. 10% EVA-g-MAH enhanced the crystal formation of PA66 in the 8% CCB/EVA-g-MAH/PA6 composites, however 20% EVA-g-MAH inhibited the crystal formation of PA66. [ABSTRACT FROM AUTHOR]

Soil sealing treatment is an effective chemical weed control method in rapeseed field. To evaluate the effects of different soil-applied herbicides on soil microorganisms in rapeseed field, 16S rRNA amplicon sequencing was used to analyze the changes in soil microbial structure and diversity after treatment with four commonly used soil-applied herbicides alachlor, acetochlor, metochlor and s-metolachlor. The results showed that soil-applied herbicide treatments could significantly reduce soil bacterial diversity in rapeseed fields, and alachlor had the greatest effect on soil bacterial diversity. However, after a period of herbicide treatment, the diversity and richness of the soil bacterial community gradually recovered. Soil-applied herbicide treatment had great influence on Actinomycetes, Acidobacteria and others in rapeseed soil, and alachlor treatment showed the greatest change in soil bacteria at phylum level compared with other herbicides. After 60 days of treatment with soil-applied herbicides, the abundances of functional bacteria related to pollutant degradation, denitrification, photosynthesis, pathogen growth inhibition and rhizosphere growth promotion were increased, whereas functional bacteria associated with the absorption of nutrients and excretion of metabolites were reduced. Overall, the results indicated that the soil-applied herbicides had a certain effect on soil microbial diversity and community structure in rapeseed field, but the effect of herbicides on soil microbial diversity gradually decreased along with the time of treatment. [ABSTRACT FROM AUTHOR]

Objective To investigate the risk factors for neonatal asphyxia in Hubei Enshi Tujia and Miao Autonomous Prefecture and establish a nomogram model for predicting the risk of neonatal asphyxia. Methods A retrospective study was conducted with 613 cases of neonatal asphyxia treated in 20 cooperative hospitals in Enshi Tujia and Miao Autonomous Prefecture from January to December 2019 as the asphyxia group, and 988 randomly selected non-asphyxia neonates born and admitted to the neonatology department of these hospitals during the same period as the control group. Univariate and multivariate analyses were used to identify risk factors for neonatal asphyxia. R software (4.2.2) was used to establish a nomogram model. Receiver operator characteristic curve, calibration curve, and decision curve analysis were used to assess the discrimination, calibration, and clinical usefulness of the model for predicting the risk of neonatal asphyxia, respectively. Results Multivariate logistic regression analysis showed that minority (Tujia), male sex, premature birth, congenital malformations, abnormal fetal position, intrauterine distress, maternal occupation as a farmer, education level below high school, fewer than 9 prenatal check-ups, threatened abortion, abnormal umbilical cord, abnormal amniotic fluid, placenta previa, abruptio placentae, emergency caesarean section, and assisted delivery were independent risk factors for neonatal asphyxia (P<0.05). The area under the curve of the model for predicting the risk of neonatal asphyxia based on these risk factors was 0.748 (95%CI: 0.723-0.772). The calibration curve indicated high accuracy of the model for predicting the risk of neonatal asphyxia. The decision curve analysis showed that the model could provide a higher net benefit for neonates at risk of asphyxia. Conclusions The risk factors for neonatal asphyxia in Hubei Enshi Tujia and Miao Autonomous Prefecture are multifactorial, and the nomogram model based on these factors has good value in predicting the risk of neonatal asphyxia, which can help clinicians identify neonates at high risk of asphyxia early, and reduce the incidence of neonatal asphyxia. [ABSTRACT FROM AUTHOR]

In order to realize the real-time detection of falling behavior in the crowd and prevent the occurrence of stampede events, an improved YOLOv5s fall behavior detection algorithm is proposed in view off the problems off real-time detection off falling behavior and insufficient feature extraction ability. The network detection accuracy is enhanced and the amount of computation is ensured by rational combination of improving the base residual block, adding a mixed domain attention mechanism to the back bone network and introducing a bidirectional feature pyramid structure to the neck The experimental results show that, compared with the original network, the detection accuracy of the proposed algorithm is improved from 94.1% to 97.0%, the accuracy value is increased from 91.2% to 95.4%, the optimized aggorithm detection speed can reach 0.028s, and the number of frames per second can reach 36.3, which meets the real-time requirements. [ABSTRACT FROM AUTHOR]

Methane, the second most prevalent greenhouse gas globally, is characterized by its high global warming potential and short atmospheric lifetime. It is primarily emitted from sectors such as coal mining, oil and gas production, agriculture, livestock rearing, and waste management. Active, prudent, and orderly control of methane emissions offers a multifaceted benefit: it mitigates global warming, enhances the economic value through the resource utilization of energy, provides environmental advantages by control of pollutants, and improves safety by reducing production accidents. Methane is also the principal greenhouse gas emitted in coal mine operations. Currently, monitoring and researching the distribution of methane emissions and their concentration within the three-dimensional space of coal mines have become a key focus in China’s methane emission control efforts, which is of significant importance for coal mining enterprises to align with national strategies. A study conducted on a high-gas mine in Shanxi and a low-gas mine in Shaanxi for methane emission monitoring and accounting utilized fixed monitoring, manual monitoring, drone monitoring, and post-mining activity monitoring to investigate the distribution of methane in high and low gas mines in China and to analyze their methane emissions. The results indicate that: ① The methane emission volumes for a certain high-gas mine in Shanxi and a low-gas mine in Shaanxi published by the U.S.-based Climate TRACE website for the year 2022 show a significant discrepancy from the results calculated using the ground measurement method, with the published annual methane emission volume for a certain low-gas mine being 10.92 times that of the ground measurement calculation. The top-down monitoring and accounting methods have been found to be insufficiently accurate and unable to provide reliable data support for carbon trading. ② In the monitoring and accounting of post-mining activities, the use of default values recommended by the IPCC results in methane emissions that are 3 to 5 times higher than those calculated using the ground measurement method, and there is a significant variation in the emissions calculated based on coal samples of different sizes and exposure durations. There is an urgent need for a unified and precise testing standard to ensure fair and accurate data for future carbon market transactions.

【Objective】Fresh bamboo shoots are bamboo shoot products that have not been blanched or pickled, with a crispy taste and refreshing flavor. However, fresh bamboo shoots breathe vigorously, which are prone to dehydration and wilting, making them difficult to keep fresh, thus affecting their sales. Spontaneous modified atmosphere packaging reduces the respiratory intensity of packaged fruits and vegetables by regulating the gas composition of the internal environment. Studying the effects of different modified atmosphere packaging treatments on the postharvest storage quality and lignification of fresh bamboo shoots could provide references for the selection of fresh-keeping packaging for fresh bamboo shoots.【Method】The peeled fresh bamboo shoots were packed in the spontaneous modified atmosphere preservation bag (thickness 20μm, O2transmission rate 11 643 cm3/m2·d·atm, water vapor transmission rate 62.586 g/m2·d), and the vacuum bag made of nylon was used as control. The packaged fresh bamboo shoots were stored in the cold storage to study the quality change and the difference of lignification degree during storage.【Result】Compared with traditional vacuum preservation techniques, spontaneous modified atmosphere packaging could significantly reduce the respiratory intensity of fresh bamboo shoots during storage by creating a low oxygen and low carbon dioxide(O2 < 5%, CO2 < 5%) environment inside the bag through the respiration of the bamboo shoots themselves and the gas permeability of the membrane material. The peak intensity was only 46.93% of that of vacuum treatment. After 21 days of storage, modified atmosphere packaging significantly inhibited the browning and membrane lipid peroxidation of bamboo shoots. The brightness of the core of packaged bamboo shoots decreased by only 6.17% compared with that upon harvest, while that of vacuum packaging decreased by 17.74%. The content of malondialdehyde in vacuum packaged bamboo shoots was 2.93 times that in modified atmosphere packaging. In terms of lignification, the lignification rates of bamboo shoots in two types of packaging began to increase after 14 days of storage. The activities of key enzymes for lignification of bamboo shoots (phenylalanine ammonia lyase, peroxidase, cinnamon dehydrogenase) peaked in vacuum packaging, and lignification intensified; however, there was no peak in the related enzyme activity of bamboo shoots in the modified atmosphere packaging, and the enzyme activity increased slowly, delaying the lignification of bamboo shoot and maintaining the crisp taste of the bamboo shoots. After 21 days of storage, the lignin content of packaged bamboo shoots decreased by 15.01% compared to vacuum packaged bamboo shoots, effectively extending the freshness period of fresh bamboo shoots.【Conclusion】The low oxygen and low carbon dioxide gas environment in the spontaneous modified atmosphere packaging bag is conducive to the storage of fresh bamboo shoots, and the quality and nutrient content are significantly better than those of vacuum packaging treatment. It has a good market prospect for fresh bamboo shoots.

In order to help relevant scientific and technological personnel in tobacco industry to accurately grasp the status on the development of tobacco fermentation, statistical analysis and patent mining were carried out based on a total of 318 tobacco fermentation patents published by the State Intellectual Property Office from 1985 to 2019. The results showed that: 1) The overall number of patent applications related to fermentation was not large, but it was slowly increasing after 2009. 2) The patent coverage from the Chinese domestic tobacco companies in this field showed quantitative advantages. China Tobacco Yunnan Industrial Limited Corporation possessed the largest number of patents, followed by China Tobacco Henan and Hubei Industrial Limited Corporations. 3) There were a large number of applications from the cooperation between domestic tobacco industry units and domestic universities, and it showed clear regional characteristics. 4) The distribution of IPC technologies in this field concentrated mainly on A24B, C12N (bacteria and their culture media) and C12R (Bacillus spp.), and their co-occurrence. 5) In terms of specific technical fields, the majority of patents involved the artificial fermentation of tobacco leaves by microorganisms or bio-enzymes, aimed at reducing irritation and increasing aroma and accelerating fermentation. These two aspects were the key points of patent coverage and the technologies were relatively mature. In terms of microbial agents, Bacillus was the most widely used, mainly including Bacillus subtilis, followed by Bacillus pumilus and Bacillus amyloliquefaciens. In terms of enzymes, cellulase, pectinase, protease and amylase were the hot spots. 6) In terms of patented technology for super fast fermentation, compared with the treating technologies of microorganisms and microorganisms + bio-enzymes mixed preparations, the use of enzyme (including complex enzymes) alone to treat tobacco leaves was more effective in shortening the fermentation time. In addition, although the present sources of microorganisms were mainly those found in tobacco leaves or tobacco-growing soil, safety assessment of biological agents ( microorganism or enzyme) used was still worthy of attention before wider applications. [ABSTRACT FROM AUTHOR]

Objective: To reveal the microbial community and its function succession principles of puffer fish (Takifugu obscurus), and to identify the dominant microbial genera on puffer fish during refrigerated storage. Methods: High-throughput sequencing was employed to investigate the microbial composition of puffer fish during refrigeration (4 ℃, 8 d), the community function was predicted by Tax4fun2, and the total volatile basic-nitrogen (TVB-N), pH and organoleptic values of puffer fish were measured as well. Results: The high-throughput sequencing demonstrated that during refrigeration the bacterial community of puffer fish succeed significantly, which were mainly composed of genera Acinetobacter, Lactobacillus, Aeromonas and Pseudomonas at the initial stage, while at the last stage composed almost of genera Pseudomonas (>91.7%), which was considered as the dominant genera on puffer fish. The α-diversity index of the community was higher at initial stage, while decreased during the storage. The microbial community function prediction results showed that the relative abundance of the amino-acid metabolism pathway and the cellular communication pathway increased at the last stage of the storage. As for the physicochemical properties, TVB-N, pH and total microbial counts increased while sensory scores decreased during the storage. Conclusion: The microbial community and its functional profile changed significantly during refrigeration, Pseudomonas was the dominant genera of puffer fish, and the above conclusion would provide theoretic guidelines for developing novel preserving technology for puffer fish.

Cigarette butts were the final byproduct after cigarette smoking, the resource utilization of cigarette butts was of great significance for reducing environmental pollution and promoting effective utilization of resources simultaneously. Based on the literature review of cigarette butts resource utilization, it was pointed out that in terms of construction materials, lightweight clay bricks, asphalt concrete and sound/wave-absorbed materials were the main products of cigarette butts. The processing capacity of cigarette butts in this field was relatively large, and the products had the characteristics of light weight and heat insulation. In terms of carbon materials, adsorbent and the electrochemical materials were the mian products of cigarette butts, and the preparation of the later material was an important way for the high-value utilization of cigarette butts. The chemical components absorbed by cigarette butts could be used to prepare products, mainly including metal corrosion inhibitors and insecticides for mosquitoes. The research on extracting chemical raw materials from cigarette butts was relatively less. The oil-water separation materials were prepared by the cellulose acetate of cigarette butts and the organosilane/polydopamine-modified products. The cellulose films or nanocrystals prepared from cellulose acetate also featured an excellent water purification performance. In the future, we could improve the infrastructure such as smoking area and smoking control area to facilitate the effective collection of cigarette butts, conduct comprehensive evaluation from the three aspects of "cost-environment- benefit" to shorten the transformation cycle between technology and industrialization, and carry out in-depth research from the development of degradable filter materials and reusable filters, so as to promote the industrialization of resource utilization of cigarette butts. [ABSTRACT FROM AUTHOR]

The surrounding rock of deep roadway is weak and the fissures are developed. Under the influence of mining disturbance, it is easy to cause dynamic disasters and the overall instability failure of coal rock combination is one of key factors inducing disasters. In order to explore the dynamic damage characteristics of the primary combined coal rock body under impact load, with the help of the split Hopkinson pressure bar and high-speed camera, raw coal, artificial combination and primary combination of coal rock are studied. Based on different hydrostatic pressure and strain rate conditions, this study explores the dynamic stress-strain, crack evolution and fracture fractal characteristics of coal rock and explores the deformation and failure characteristics of coal rock using macroscopic fracture fractal and microscopic electron microscope scanning. The study shows that ① the dynamic stress-strain of raw coal, artificial combination and primary combination of coal rock is significantly nonlinear and the plastic stage of primary coal rock is similar to “plastic platform”. ② Under impact load, the strain rate effect of dynamic compressive strength of coal rock is significant and the dynamic compressive strength and hydrostatic pressure of raw coal, primary combined coal rock show a trend of first increasing and then decreasing. The critical values of hydrostatic pressure (low pressure strengthening and high pressure weakening) are 8 MPa and 10 MPa and the artificial combined coal rock and hydrostatic pressure show a positive correlation trend. ③ Under the impact load, the crack initiations of primary and artificial combined coal rock occur in the coal composition area far from the interface of coal rock. The combined coal-rock interface significantly affects the deformation and failure behavior of the sample and when the impact velocity≥10 m/s, the overall instability failure of coal rock components can occur in the original combined coal rock, while only the coal component failure occurs in the artificial combined coal rock under the same disturbance. Besides, only when the impact velocity≥14 m/s, the tip stress of the crack is greater than the strength of the coal rock, which can penetrate the artificial interface and lead to the overall crushing. The original interface has a “guiding effect” on the crack penetration of the sample, which is easy to induce crack propagation to form a macroscopic fracture surface. ④ The crushing degrees of raw coal, original coal and artificial coal rock increase with the increase of impact velocity and the crushing particle size tends to be granular and powder. Under the same disturbance, the degrees of fragmentation of coal components in three types of coal rocks show a relationship: primary-coal components > artificial-coal components > raw coal.

Peroxisome proliferators-activated receptors (PPARs) are the primary targets of perflurooctane sulfonate (PFOS). However, three subtypes of PPARs may exert diverse effects on the toxic response induced by PFOS, whereas related mechanism remains unclear. In the present study, an in vitrodifferentiation model of human bone marrow-derived mesenchymal stem cells (hBMSCs) was employed to evaluate the interference of PFOS exposure on PPARs subtypes and the association with abnormal cell differentiation. The results showed that PFOS induced upregulation of mRNA expression of PPARα, PPARβ, and PPARγ at concentrations of 0.1, 1 and 10 μmol⋅L-1, up to 6.31 folds, 6.44 folds, and 15.4 folds in the treatment group of 1 μmol⋅L-1 of PFOS compared to vehicle control. Being consistent with PPARγ activation, PFOS promoted adipogenic differentiation and increased lipid formation in hBMSCs. Meanwhile, PFOS exposure inhibited osteogenic differentiation, decreased calcium nodule formation, and reduced the expression of runt-related transcription factor 2 (Runx2) and alkaline phosphatase (ALP), which are the marker genes of early osteogenic differentiation. In addition, the enrichment analysis of differentially expressed genes affected by PFOS in the gene profile of hBMSCs revealed that the disturbed pathways were mainly related to cell differentiation, bone metabolism and lipid metabolism. In contrast, PFOS exposure increased the mRNA expression of osteoprotectin, consistent with the upregulation of PPARβ. The results demonstrate that the activation of PPARs subtypes by PFOS may exert different effects on stem cell differentiation. Further research is necessary to gain an insight to understand the toxicity mechanism of per- and polyfluoroalkyl compounds. [ABSTRACT FROM AUTHOR]

To study the deformation and failure law of roadway surrounding rock with weak interlayer under dynamic and static loads, taking the deep transportation roadway of Longfeng Coal Mine as the research object, the mechanical deformation characteristics of roadway surrounding rock with weak interlayer under dynamic and static loads is analyzed by using FLAC3D numerical simulation software, and the support optimization scheme is proposed combined with the actual roadway situation on site. The results show that the influence of dynamic load on roadway both sides is greater than that of roadway roof and floor. Compared with the static load, the deformation and failure range of roadway surrounding rock under dynamic load is more sufficient, the weak interlayer is easier to separate from the adjacent rock stratum and a dangerous area with caving risk is formed in the roadway roof. The stability of surrounding rock is obviously improved under the new support measures, which ensures the safe production of the mine.

The research and development (R&D) project is a complex network composed by interdependent elements in different domains such as the product, function, organization and process domain. In order to describe the relationship among elements in cross domains simultaneously, this paper introduces the extended domain mapping matrix (EDMM) to analyze the dependency relationships among "team-product-function". Furthermore, this paper introduces the extended multi-domain matrix (EMDM) and builds a quantitative model for deriving dependency strengths in the organization design structure matrix (DSM) through function DSM, product DSM and EDMM. In order to optimize the organization architecture for reducing the complexity of management, an improved two-stage clustering criterion model is proposed for clustering organization DSM, of which the first-stage clustering criterion is the maximization of uadded internal dependency and external dependency ration55 (AIDER) and the second-stage clustering criterion is the minimization of the total coordination cost. An industrial example is provided to illustrate the proposed model. Results indicate that the clustered organization DSM can reduce coordination cost significantly compared to previous clustering methods. [ABSTRACT FROM AUTHOR]

In recent years, sclerotia mycelial germination (led to Sclerotinia stem rot) was found at oilseed rape seedling stage in Sichuan and Hubei provinces. To better understand this new type of sclerotinia rot, studies were carried out in relation to myceliogenic germination. Rapid water uptake was observed in sclerotia during the first hour and sclerotia were saturated in approximately 2 h. Saturated sclerotia had doubled in weight and gemina ted myceliogenically within 4 days of incubation without exogenous nutrients at 25 °C. Almost all sclerotium germinated myceliogenically within 11 d of incubation. High soil moisture was favorable for sclerotia to germinate myceliogenically. Younger sclerotia germinated faster. But after 9 d, the difference of germinating speed was not significant. Sclerotia could germinate myceliogenically at 10.0-30.0°C, and germinated rapidly at 20.0-27. 5°C. The germination rate of sclerotia decreased with pH increasing. The highest germination rate was observed at pH 3 on the 4th day. Field inoculation test showed that sclerotia germinated myceliogenically. The mycelial germination caused Sclerotinia stem rot before initial flowering stage. The highest disease index reached 11.7% on rapeseed seedling. [ABSTRACT FROM AUTHOR]

DOI：10.3969/j.issn.1672⁃6731.2020.04.018

[Objective]The pathogen separation and molecular identification of the infected tomato plants were conducted and the biological characteristics were analyzed to provide theoretical references for breeding the resistant varieties and controlling the tomato bacterial wilt. [Method]Ralstonia solanacearum strains were isolated using the plate dilution method, and the 16S rDNA sequence, carbohydrate utilization, pathogenicity, phylotype and sequevar of the strains were studied. [Result]Strains Tom 1-Tom 9 isolated from tomato plants were identified as Ralstonia solanacearum based on the results of colony characteristics on TTC medium, pathogenicity inoculation test and molecular identification. The result of carbohydrate utilization and pathogenicity tests showed that the 9 strains were able to oxidize three hexoses and three disaccharides, and could strongly infect tobacco, potato, tomato, pepper and eggplant. The results of phylotype multiplex PCR indicated the specific 280 and 144 bp bands were amplified from all 9 strains, respectively. [Conclusion]Nine strains of Ralstonia solanacearum isolated from tomato infected with bacterial wilt has been identified and belong to biovar III, race 1, phylotype 1 and sequcvar 17. [ABSTRACT FROM AUTHOR]

From October 2007 to November 2008, an in situ mesh bag experiment was conducted to study the leaf litter decomposition and nutrient release of forest stands Populus alba var. pyramidalis, Amorpha fruticosa, and P. alba var. pyramidalis + A. fruticosa in a shelter belt in Karamay, Xinjiang. It was observed that the mass loss rate of leaf litter differed with tree species, and was significantly affected by leaf litter composition. The leaf litter of P. alba var. pyramidalis + A. fruticosa was more easily decomposed than that of the other two mono-dominance forest trees. The analysis with improved Olson?s exponential model indicated that P. alba var. pyramidalis leaf litter had the lowest decomposition coefficient (k =0.167), while P. alba var. pyramidalis + A. fruticosa leaf litter had the highest one (k = 0.275). According to the model, it would cost for about 2.41-4.19 years and 10.79-17.98 years to have 50% and 95% decomposition of the three kind leaf litters, respectively. The residual rates of nitrogen, phosphorus, and potassium in the three kind leaf litters differed with decomposition period. After one year decomposition, potassium was wholly released, while nitrogen and phosphorus were immobilized or enriched via the absorption from surrounding environment. Except that the A. fruticosa leaf litter had a decreased organic carbon decomposition rate in the mid period of decomposition, the leaf litters of P. alba var. pyramidalis and P. alba var. pyramidalis + A. fruticosa all had an increasing organic carbon decomposition rate with the decomposition, which was about 35.5% -44.2% after one year decomposition. The C/ N value of the leaf litters had a decreasing trend, and the decrement was smaller in the early and mid periods but larger in the late period of decomposition. [ABSTRACT FROM AUTHOR]

In order to explore the ways for promoting litter decomposition in urban protective greenbelts of arid zone, litter falls were collected from the protective greenbelts in north suburb of Karamay, Xinjiang, and a composting experiment with the inoculation of three kinds of microbial agents, i.e., Qingzhu, Jiegan, and Sufu, was carried out for 198 days in late October 2007. At the early stage (0-30 d) of composing, inoculating microbial agents promoted the decomposition of the litter falls, and the effect of Sufu agent was significant, compared with CK. The N, P, and Ca concentrations in the composing litter falls increased persistently with time. By the end of the experiment, the nutrient concentrations in the composed litter falls were 14.2%-252.9% higher than their initial values. During the whole composing process, the decomposition rate of the litter falls organic C increased continuously, and the C/N ratio decreased gradually. It was suggested that inoculating microbial agents could accelerate the composting process, and increase the nutrient concentrations in composted litter falls. Among the three test microbial agents, Jiegan agent was the best one. [ABSTRACT FROM AUTHOR]

The article examines the attributes of the 45 Gallibacterium anatis strains of chickens in Zhengzhou, China. Researchers isolated the strains from 10 tissues of 101 chickens using morphological observation, Viteck 32 automatic bacterial identification system. Of the 45 isolates, researchers found that 43 came from hens with salpinghitis and two from hens with respiratory symptoms. They also discovered that all the 45 strains are resistance to cidomycin, ampicillin, norfloxacin and laevomycetin.

The article presents a study on the genetic heterogeneity and origin of ten porcine circovirus (PCV) type 2 strains in swines in Henan, China. According to the study, the PCV2 strains were nearly related with other areas of China. The genome of PCV2 strains shows a stable genetic homogeneity and the existence of porcine circovirus-associated disease is not related to the emergence of PCV2 genotype.

Objective To retrospectively analyze and investigate the conversion of cognitive function and characteristics of hydrogen proton magnetic resonance spectroscopy (1H-MRS) in patients with mild cognitive impairment (MCI). Methods Mini-Mental State Examination (MMSE) and Montreal Cognitive Assessment (MoCA) were used to assess the cognitive function of 75 MCI patients and 17 normal controls who were matched in sex, age and education with MCI patients. 1H-MRS was performed in the left hippocampus and left frontal lobe with 3.0T MRI respectively to evaluate related metabolites in the brain, including N-acetyl-aspartate (NAA), choline (Cho), creatine (Cr), myo-inositol (mI) and glutamate complex (Glx). Results Compared with normal control group, the Glx/Cr ratio of left hippocampus and left frontal lobe in MCI group were significantly lower (P = 0.030, 0.030). By the end of follow-up, 7 of 75 subjects (9.33%) in MCI group had converted to Alzheimer's disease (MCI-AD subgroup), 55 cases (73.33%) had no change on their cognitive function (MCI-MCI subgroup), and 13 cases (17.33%) were considered returning to normal (MCI-normal subgroup). The Glx/Cr ratio of MCI-MCI subgroup was significantly higher than that of MCI-AD subgroup (P = 0.040). In normal control group, 13 cases (13/17) had no change on their cognitive function, and 2 cases (2/17) progressed into MCI. However, none of them converted to AD. Conclusions The decline of Glx/Cr ratio in left hippocampus and left frontal lobe could possibly be the sensitive biological indicator of worsened cognitive function in MCI patients. Further study with enlarged samples and prolonged follow-up is still needed. DOI: 10.3969/j.issn.1672-6731.2016.06.005

Existing face recognition methods cannot effectively eliminate the influence of corrupted features caused by occlusion. As the features flow deeper, the corrupted features get entangled with the effective features used for identity classification, which affects the recognition results. To address the problem, this paper designs an occluded face recognition method based on segmentation and multi-stage mask learning strategy. The model consists of three components: occlusion detection and segmentation, feature extraction, and mask learning unit. The proposed method only needs one end-to-end process to learn feature masks and deep occlusion-robust features without relying on additional occlusion detectors. The mask learning units take different sizes of occlusion segmentation representations and facial features of different stages as input, generate corresponding feature masks for different stages of feature extraction, and effectively eliminate the influence of corrupted features caused by occlusion at each stage of feature extraction through mask operations. Finally, a feature pyramid is constructed to fuse features of different stages for identity classification. Experimental results show that the proposed method can effectively improve the accuracy of occluded face recognition. The accuracy on the occluded LFW dataset and the real masked datasets MFR2 and Mask_whn reach 98.77%, 96.70% and 81.53%, respectively, which has an accuracy improvement of 2.04, 0.48 and 4.44 percentage points compared with the existing mainstream methods.

Aiming to distributed computing and data centralizing storage in large-scale network computing environments and combining sparse and bursting characteristic of COW(copy-on-write) disk storing modified data blocks,the distributed COW network disk architecture was presented.The system building process of network computing environments was speeded up by apportioning the aggregation spending that server manages all related COW disks of client hosts to each client host.A improving 64bit bitmap compress arithmetic was designed to reduce the size of COW disk’s bitmap,so server disk space was saved and the network communication spending of distributed COW disk was less.The modified prefetching arithmetic based on COW bursting blocks was presented to improve the hit rate of Cache relating with distributed COW disk.Experiments on the prototype show that the distributed COW mechanism can effectively reduce system building latency of multi-client hosts network computing environment based on improving COW bitmap compress and prefetching arithmetic.

A comprehensive study on the temporal and spatial distribution of H2S accumulations and the geochemical characteristics of sour gas fields (reservoirs) in the Sichuan Basin has been conducted. It has been followed by a series of carefully designed simulation experiments to elucidate an H2S formation mechanism which is able to predict the distribution of H2S. In some reservoirs, for example P2ch(T1f, have sufficient magnesic SO42( and abundant hydrocarbons (palaeo pools) present at sufficiently high temperatures to cause thermochemical sulfate reduction (TSR). This is the major origin of abundant H2S in large to medium scale gas fields. The formation mechanism of highly sour gas fields (reservoirs) is an in-situ reaction under conditions where sufficient source, enough energy supply, suitable reservoir volume and severely reducing environments occur. However, in some areas or strata, such as slope belts or on continental shelf deposits, or formations such as the Jialingjia and Leikoupo Formations, which are dominantly compact carbonatite and have contemporaneously different facies, it is difficult to form abundant H2S. These formations lack a source of sulphur and energy compared to the P2ch(T1f reef flat facies reservoirs. Even though highly sour natural gas migrating from the P2ch(T1f reservoirs is present, H2S is often consumed due to long distance migration and results in hydrocarbon-rich sweet natural gas. This study predicts that the Heichiliang reef flat facies sedimentary zone in northeastern Sichuan to have highly sour natural gas reservoirs. 摘要: ： 通过对四川盆地含硫天然气田（藏）时空分布、地球化学特征及模拟实验结果等的综合研究，揭示H2S形成机理并进行分布预测。P2ch—T1f储集层中足够的含镁SO42-溶液和丰富的烃类（古油藏）在高温条件下发生硫酸盐热化学还原反应（TSR）是四川盆地大中型天然气田中大量H2S形成的主要途径；充足的物源基础、足够的能量供给、适宜的储集空间和苛刻的还原环境下发生的原地反应是高含硫天然气田（藏）形成的主要机制。而以与P2ch—T1f礁滩相储集层同期异相的致密碳酸盐岩为主的斜坡带、陆棚内部以及嘉陵江组、雷口坡组等因缺乏物源、能量等难以形成高丰度H2S，即使有自P2ch—T1f储集层运移而来的高含硫天然气，也因远距离运移H2S被消耗而变为富烃低硫天然气。预测川东北黑池梁礁滩相沉积区有发育高含硫天然气藏的可能性。图4表3参30 Key words: northeastern Sichuan, H2S, TSR, enrichment mechanism, highly sour gas field